著者
相山 律男 永井 久子 沢田 誠吾 横倉 輝男 糸川 秀治 中西 守
出版者
The Pharmaceutical Society of Japan
雑誌
Chemical and Pharmaceutical Bulletin (ISSN:00092363)
巻号頁・発行日
vol.40, no.10, pp.2810-2813, 1992-10-25 (Released:2008-03-31)
参考文献数
16
被引用文献数
12 16

Self-association of irinotecan hydrochloride (CTP-11) in an aqueous solution was studied using UV, circular dichroism (CD), 1H-NMR and the quasi-elastic light scattering (QLS) method. The UV spectra showed a hypochromic effect in the aqueous solution. In the CD spectra, typically positive Davydov splitting was observed and the Δε value was reduced sigmoidally when the concentraion of CTP-11 was decreased. In the 1H-NMR, the aromatic signals of higher concentration shifted to a diamagnetic direction compared with those of lower concentration. These observations suggested that CPT-11 molecules are present as monomer in the lower concentration, and the self-association with positive helicity occurs by vertical stacking more than 10 μM of concentration. Its molecules form complete aggregates at more than 2 mM of the concentration. Results of QLS which coincided in the prediction of partition coefficient experiments suggested that CPT-11 molecules formed dimer under the condition. By the regression analysis of CD spectral data, the equilibrium constant for the self-association was calculated to be 2.41×10-4 M-1.
著者
沢田 誠吾 宮坂 貞 荒川 基一
出版者
The Pharmaceutical Society of Japan
雑誌
Chemical and Pharmaceutical Bulletin (ISSN:00092363)
巻号頁・発行日
vol.26, no.1, pp.275-287, 1978-01-25 (Released:2008-03-31)
被引用文献数
2 2

1-(Substituted-phenyl)-2, 3-tetramethylenepyrrolo [2, 1-b] benzothiazoles (IV-2-IV-17) were synthesized from the correspoding 3-(substituted-phenyl) thiazolo [2, 3-b] benzothiazolium perchlorates (III) by the reaction of 1-morpholino-1-cyclohexene, an enamine. On reaction with cuprous cyanide p-substituted bromobenzene (IV-2) furnished benzonitrile (IV-23), which was converted into the corresponding 1-phenyl derivatives (IV) with various aliphatic functional groups at the para position of the phenyl moiety. On reaction with methylmagnesium iodide and subsequent acid hydrolysis IV-23 was converted into acetophenone (IV-24), which reacted with methyltriphenylphosphylene to give 2-phenylpropylene (IV-38). Hydroboration of IV-38 afforded 2-phenylpropanol (IV-39), which was oxidized into the corresponding propionic acid (IV-43), the sulfur atom being oxidized at the same time into sulfoxide. Deoxygenation of the ester (IV-44) was successfully carried out with PBr3 to obtain the desired α-phenyl substituted propionic acid ester (IV-45).
著者
沢田 誠吾 宮坂 貞 荒川 基一
出版者
The Pharmaceutical Society of Japan
雑誌
Chemical and Pharmaceutical Bulletin (ISSN:00092363)
巻号頁・発行日
vol.25, no.12, pp.3370-3375, 1977-12-25 (Released:2008-03-31)
被引用文献数
5 5

Seventeen 3-(substituted-phenyl) thiazolo [2, 3-b] benzothiazolium perchlorates (3) were synthesized by acid-cyclization of the ketosulfides (2), which were prepared by alkylation of 2-mercaptobenzothiazole sodium salt with substituted phenacyl halides (1). Some of the phenacyl halides were prepared by chloroacetylation of substituted benzenes, and the others by bromination of the corresponding substituted acetophenones.
著者
沢田 誠吾 八重樫 隆 古田 富雄 横倉 輝男 宮坂 貞
出版者
The Pharmaceutical Society of Japan
雑誌
Chemical and Pharmaceutical Bulletin (ISSN:00092363)
巻号頁・発行日
vol.41, no.2, pp.310-313, 1993-02-15 (Released:2008-03-31)
参考文献数
22
被引用文献数
13 20

7-Ethylcamptothecin (1d), a model which does not have any site on the A-ring for further modification was converted into water-soluble derivatives by opening the E-ring lactone. 1d was heated in N, N-dimethylenediamine to yield amide 2a, and this was then acylated to furnish 3a-q, which were soluble in water as their HCl salts. The propionyl (3b), butyryl (3c) and methylthiopropionyl (3h) derivatives showed higher activity than the sodium salt of 1d. The acyl group makes the derivatives more lipophilic, and ease of hydrolysis of amide 2a to 1d is thought to be necessary for significant activity.
著者
八重樫 隆 沢田 誠吾 古田 富雄 横倉 輝男 山口 健太郎 宮坂 貞
出版者
The Pharmaceutical Society of Japan
雑誌
Chemical and Pharmaceutical Bulletin (ISSN:00092363)
巻号頁・発行日
vol.41, no.5, pp.971-974, 1993-05-15 (Released:2008-03-31)
参考文献数
10
被引用文献数
6 10

The structure of the N-amino pyridone (4a) obtained by the reaction of camptothecin (1a) with hydrazine was determined by X-ray crystallography. A mixture of 7-etylcamptothecin (1b) and hydrazine hydrate was stirred at room temperature, and the hydrazide (2b) was isolated as its diacetate 2c. Treatment of the 17-O-acetyl amide (5a) with hydrazine gave 1b (74% yield) and the N-amino lactam 6 (11% yield). Compounds with bulky acyl groups, 5c-e, gave 6 in modest yields. The N-amino lactam 6 was smoothly dehydrated into the pyridone 4d by refluxing in hydrazine hydrate.
著者
八重樫 隆 野方 健一郎 沢田 誠吾 古田 富雄 横倉 輝男 宮坂 貞
出版者
The Pharmaceutical Society of Japan
雑誌
Chemical and Pharmaceutical Bulletin (ISSN:00092363)
巻号頁・発行日
vol.40, no.1, pp.131-135, 1992-01-25 (Released:2008-03-31)
参考文献数
19
被引用文献数
9 10

Water-soluble derivatives having the lactone ring intact were synthesized starting from 7-ethyl-10-hydroxycamptothecin (1). Glycosides (2) of the phenolic hydroxyl group of 1 were obtained by reaction with acetylated α-bromosugars in acetone or aqueous acetone in the presence of potassium carbonate, followed by deprotection.Phosphates (3) were prepared by reaction of 1 with phosphoryl chloride in pyridine or with dibenzylchlorophosphoridate.Sulfates (4) were obtained by reaction of 1 with sulfur trioxide-pyridine complex in the presence of a tertiary amine.The organic ammonium salts of monophosphate (3p) and sulfates (4a and 4b) showed significant activity against L1210 in vivo.
著者
沢田 誠吾 松岡 俊一 野方 健一郎 永田 洋 古田 富雄 横倉 輝男 宮坂 貞
出版者
The Pharmaceutical Society of Japan
雑誌
Chemical and Pharmaceutical Bulletin (ISSN:00092363)
巻号頁・発行日
vol.39, no.12, pp.3183-3188, 1991-12-25 (Released:2008-03-31)
参考文献数
28
被引用文献数
39 57

20(S)-Camptothecin derivatives having nitro, amino, chloro, bromo, hydroxyl and methoxyl groups in the A-ring were synthesized. B-Ring hydrogenated camptothecin (2a) was converted into 10-hydroxycamptothecin (6e) by treatment with lead tetraacetate in trifluoroacetic acid. 10-Substituted derivatives (6) were obtained by a photoreaction of N-oxides (9). The cytotoxicity o the A-ring modified camptothecins was evaluated against KB cells in vitro and leukemia L1210 in mice. 7-Ethyl-10-hydroxycamptothecin (6i) was identified as a potential derivative for further modification.
著者
沢田 誠吾 岡島 悟 相山 律男 野方 健一郎 古田 富雄 横倉 輝雄 杉野 栄一 山口 健太郎 宮坂 貞
出版者
The Pharmaceutical Society of Japan
雑誌
Chemical and Pharmaceutical Bulletin (ISSN:00092363)
巻号頁・発行日
vol.39, no.6, pp.1446-1454, 1991-06-25 (Released:2008-03-31)
参考文献数
18
被引用文献数
144 197

Nevel 36 derivatives (6), bonding the phenolic hydroxyl group of 7-ethyl-10-hydroxycamptothecin (4) with diamines through a monocarbamate linkage, were synthesized and their antitumor activity was evaluated in vivo. The derivatives were soluble in water as their HC1 salts wiht the E lactone ring intact and exhibited significant antitumor activity. One of the derivatives, 6-27 showed excellent activity against L1210 leukemia and other murine tumors.The structure of its hydrochloride trihydrate (CPT-11) was determined by spectroscopic and crystallographic methods.
著者
沢田 誠吾 野方 健一郎 古田 富雄 横倉 輝男 宮坂 貞
出版者
The Pharmaceutical Society of Japan
雑誌
Chemical and Pharmaceutical Bulletin (ISSN:00092363)
巻号頁・発行日
vol.39, no.10, pp.2574-2580, 1991-10-25 (Released:2008-03-31)
参考文献数
14
被引用文献数
44 56

A radical substitution reaction of 20(S)-camptothecin (1) with methanol furnished 7-hydroxymethylcamptothecin (2). Reaction of 1 with primary alcohols higher than methanol gave 7-alkylcamptothecins (4), of which alkyl groups were one carbon less than the alcohols used and also 7-hydroxyalkylcamptothecins (5). For the preparation of 7-alkylcamptothecin (4), aldehydes were used as a radical source and several alkylated derivatives were synthesized. 7-Acyloxymethyl derivatives (6), 7-carbaldehyde (7), iminomethyl derivatives (10), acid (11), esters (12) and amides (13) were synthesized starting from 2. 7-Ethyl-(4b) and 7-propylcamptothecin (4c), acyloxymethyl compounds 6a, 6c and ethyl ester (12b) exhibited higher antitumor activity than 1 against L1210 in mice.
著者
沢田 誠吾 野方 健一郎 古田 富雄 横倉 輝男 宮坂 貞
出版者
公益社団法人日本薬学会
雑誌
Chemical & pharmaceutical bulletin (ISSN:00092363)
巻号頁・発行日
vol.39, no.10, pp.2574-2580, 1991-10-25

A radical substitution reaction of 20(S)-camptothecin (1) with methanol furnished 7-hydroxymethylcamptothecin (2). Reaction of 1 with primary alcohols higher than methanol gave 7-alkylcamptothecins (4), of which alkyl groups were one carbon less than the alcohols used and also 7-hydroxyalkylcamptothecins (5). For the preparation of 7-alkylcamptothecin (4), aldehydes were used as a radical source and several alkylated derivatives were synthesized. 7-Acyloxymethyl derivatives (6), 7-carbaldehyde (7), iminomethyl derivatives (10), acid (11), esters (12) and amides (13) were synthesized starting from 2. 7-Ethyl-(4b) and 7-propylcamptothecin (4c), acyloxymethyl compounds 6a, 6c and ethyl ester (12b) exhibited higher antitumor activity than 1 against L1210 in mice.
著者
八重樫 隆 野方 健一郎 沢田 誠吾 古田 富雄 横倉 輝男 宮坂 貞
出版者
公益社団法人日本薬学会
雑誌
Chemical & pharmaceutical bulletin (ISSN:00092363)
巻号頁・発行日
vol.40, no.1, pp.131-135, 1992-01-25

Water-soluble derivatives having the lactone ring intact were synthesized starting from 7-ethyl-10-hydroxycamptothecin (1). Glycosides (2) of the phenolic hydroxyl group of 1 were obtained by reaction with acetylated α-bromosugars in acetone or aqueous acetone in the presence of potassium carbonate, followed by deprotection.Phosphates (3) were prepared by reaction of 1 with phosphoryl chloride in pyridine or with dibenzylchlorophosphoridate.Sulfates (4) were obtained by reaction of 1 with sulfur trioxide-pyridine complex in the presence of a tertiary amine.The organic ammonium salts of monophosphate (3p) and sulfates (4a and 4b) showed significant activity against L1210 in vivo.
著者
沢田 誠吾 八重樫 隆 古田 富雄 横倉 輝男 宮坂 貞
出版者
公益社団法人日本薬学会
雑誌
Chemical & pharmaceutical bulletin (ISSN:00092363)
巻号頁・発行日
vol.41, no.2, pp.310-313, 1993-02-15

7-Ethylcamptothecin (1d), a model which does not have any site on the A-ring for further modification was converted into water-soluble derivatives by opening the E-ring lactone. 1d was heated in N, N-dimethylenediamine to yield amide 2a, and this was then acylated to furnish 3a-q, which were soluble in water as their HCl salts. The propionyl (3b), butyryl (3c) and methylthiopropionyl (3h) derivatives showed higher activity than the sodium salt of 1d. The acyl group makes the derivatives more lipophilic, and ease of hydrolysis of amide 2a to 1d is thought to be necessary for significant activity.
著者
沢田 誠吾 野方 健一郎 古田 富雄 横倉 輝男 宮坂 貞
出版者
公益社団法人 日本薬学会
雑誌
CHEMICAL & PHARMACEUTICAL BULLETIN (ISSN:00092363)
巻号頁・発行日
vol.39, no.10, pp.2574-2580, 1991
被引用文献数
56

A radical substitution reaction of 20(S)-camptothecin (1) with methanol furnished 7-hydroxymethylcamptothecin (2). Reaction of 1 with primary alcohols higher than methanol gave 7-alkylcamptothecins (4), of which alkyl groups were one carbon less than the alcohols used and also 7-hydroxyalkylcamptothecins (5). For the preparation of 7-alkylcamptothecin (4), aldehydes were used as a radical source and several alkylated derivatives were synthesized. 7-Acyloxymethyl derivatives (6), 7-carbaldehyde (7), iminomethyl derivatives (10), acid (11), esters (12) and amides (13) were synthesized starting from 2. 7-Ethyl-(4b) and 7-propylcamptothecin (4c), acyloxymethyl compounds 6a, 6c and ethyl ester (12b) exhibited higher antitumor activity than 1 against L1210 in mice.
著者
沢田 誠吾 松岡 俊一 野方 健一郎 永田 洋 古田 富雄 横倉 輝男 宮坂 貞
出版者
公益社団法人 日本薬学会
雑誌
CHEMICAL & PHARMACEUTICAL BULLETIN (ISSN:00092363)
巻号頁・発行日
vol.39, no.12, pp.3183-3188, 1991
被引用文献数
57

20(S)-Camptothecin derivatives having nitro, amino, chloro, bromo, hydroxyl and methoxyl groups in the A-ring were synthesized. B-Ring hydrogenated camptothecin (2a) was converted into 10-hydroxycamptothecin (6e) by treatment with lead tetraacetate in trifluoroacetic acid. 10-Substituted derivatives (6) were obtained by a photoreaction of N-oxides (9). The cytotoxicity o the A-ring modified camptothecins was evaluated against KB cells in vitro and leukemia L1210 in mice. 7-Ethyl-10-hydroxycamptothecin (6i) was identified as a potential derivative for further modification.
著者
沢田 誠吾 岡島 悟 相山 律男 野方 健一郎 古田 富雄 横倉 輝雄 杉野 栄一 山口 健太郎 宮坂 貞
出版者
公益社団法人日本薬学会
雑誌
Chem. Pharm. Bull. (ISSN:00092363)
巻号頁・発行日
vol.39, pp.1446-1454, 1991
被引用文献数
9

Nevel 36 derivatives (6), bonding the phenolic hydroxyl group of 7-ethyl-10-hydroxycamptothecin (4) with diamines through a monocarbamate linkage, were synthesized and their antitumor activity was evaluated in vivo. The derivatives were soluble in water as their HC1 salts wiht the E lactone ring intact and exhibited significant antitumor activity. One of the derivatives, 6-27 showed excellent activity against L1210 leukemia and other murine tumors.The structure of its hydrochloride trihydrate (CPT-11) was determined by spectroscopic and crystallographic methods.
著者
八重樫 隆 沢田 誠吾 永田 洋 古田 富雄 横倉 輝男 宮坂 貞
出版者
公益社団法人 日本薬学会
雑誌
CHEMICAL & PHARMACEUTICAL BULLETIN (ISSN:00092363)
巻号頁・発行日
vol.42, no.12, pp.2518-2525, 1994
被引用文献数
42

Twenty-six novel A-ring-modified 7-ethylcamptothecins (6) were synthesized by Friedlander's condensation of the chiral tricyclic ketone (5) with aminopropiophenones (4). The compounds substituted with fluorine at the 11 position showed strong cytotoxicity to KB and L1210 cells. The 11-fluoro derivatives also exhibited strong inhibitory activity on DNA topoisomerase I. Nine compounds 6 with four to ten times stronger cytotoxicity than that of camptothecin were selected and converted into water-soluble 17-O-acyl amide derivatives (8). Compounds 8e (10-Me, O-COCH<SUB>2</SUB>CH<SUB>2</SUB>SCH<SUB>3</SUB>) and 8f (11-F, O-COC<SUB>2</SUB>H<SUB>5</SUB>) showed activity towards Meth A in mice that was comparable to that of CPT-11, at lower doses than CPT-11.
著者
八重樫 隆 沢田 誠吾 永田 洋 古田 富雄 横倉 輝男 宮坂 貞
出版者
公益社団法人日本薬学会
雑誌
Chemical & pharmaceutical bulletin (ISSN:00092363)
巻号頁・発行日
vol.42, no.12, pp.2518-2525, 1994-12-15

Twenty-six novel A-ring-modified 7-ethylcamptothecins (6) were synthesized by Friedlander's condensation of the chiral tricyclic ketone (5) with aminopropiophenones (4). The compounds substituted with fluorine at the 11 position showed strong cytotoxicity to KB and L1210 cells. The 11-fluoro derivatives also exhibited strong inhibitory activity on DNA topoisomerase I. Nine compounds 6 with four to ten times stronger cytotoxicity than that of camptothecin were selected and converted into water-soluble 17-O-acyl amide derivatives (8). Compounds 8e (10-Me, O-COCH_2CH_2SCH_3) and 8f (11-F, O-COC_2H_5) showed activity towards Meth A in mice that was comparable to that of CPT-11,at lower doses than CPT-11.